The present invention relates to machine tools in general, and more specifically to apparatus for holding and automatically exchanging tools used in a machine tool operation.
As is well known by those skilled in the art, numerically controlled machine tools have been used widely to perform various complex operations on a workpiece. Machine tools using numerical controls can be programmed to perform various operations in succession, some of which require successive tool changes.
Both automatic tool changing devices and manual "quick change" devices have been used to increase the speed and efficiency of machine tools. Some manual quick change devices are relatively simple to operate and provide both a quick release or quick engagement of a tool. However, the manual devices lack efficiency because of the necessity of a manual change.
Previously used automatic tool changing devices have been complex, often having several extra arms which grasp and handle tools, transferring tools between a machine tool spindle and a storage rack. These devices typically require extra machine tool motions to operate the additional arms which add to the time required for a tool change. Furthermore, many previously used devices require extra space to allow uninhibited travel of the additional components. Auxiliary motors are typically required to operate tool change arms, etc. Such motors are costly, and can be bulky and require additional space.